#include<bits/stdc++.h>
using namespace std;

// 【题目】力扣0704.二分查找
// 【难度】简单
// 【提交】https://leetcode.cn/problems/binary-search/submissions/669072794/?envType=problem-list-v2&envId=binary-search
// 【标签】数组；二分查找

class Solution {
public:
    int search(vector<int>& nums, int target) {
        int left = 0, right = nums.size() - 1;
        while (left <= right) {
            int mid = (right + left) / 2;
            int num = nums[mid];
            if (num == target) {
                return mid;
            } else if (num > target) {
                right = mid - 1;
            } else (num < target){
                left = mid + 1;
            }
        }
        return -1;     
    }
};